Serum anti-Müllerian hormone (AMH) levels decrease early during the transition to menopause and women with type 1 diabetes mellitus (DM1) experience menopause at a younger age. We hypothesized that older women with DM1 will have lower AMH levels than controls. We studied ovarian function in women with DM1 (n = 66) and healthy controls (n = 58), all <45 years old. Steroids, gonadotrophins, AMH and inhibin B levels were measured during the follicular phase. Piece-wise regression analysis demonstrated that AMH levels begin to decrease at 33 years of age in both groups. This age limit was used to compare data in both groups. AMH levels were lower in DM1 women than in controls >33 years (4.1 +/- 4.2 versus 9.5 +/- 7.9 pmol/l, mean +/- SD, P = 0.006). A higher proportion of women with DM1 showed AMH levels in the menopausal range compared with controls (16.7% versus 3.4%, respectively, P = 0.02). For all patients, those with DM1 exhibited lower inhibin B levels than controls (89.3 +/- 51.7 versus 113.2 +/- 76.0 ng/ml, P < 0.05). FSH and estradiol were similar in both groups. Regression analysis showed an earlier decline in AMH levels in women with DM1 than controls. Even after age adjustment, DM1 was a significant factor for the determination of inhibin B and AMH levels. Lower AMH levels in women with DM1 during the fourth decade of life suggest the presence of an earlier decline in the ovarian follicle pool in these women. Further studies are needed to evaluate the mechanism of this complication.
